Velopedia Bicycle Archive

2004 Trek 820

Original specifications: Mountain Mix drivetrain · 26" wheels · legacy reference geometry.

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At a glance

Model year
2004
Category
Mountain
Original MSRP
$219.99
Sizes
13", 15.5", 17.5", 19.5", 21.5", womens 13", womens 17.5"
Colors
Black/Red, Blue/Silver
Geometry
Legacy reference
In this record
25 specifications · archived image · original MSRP · geometry
Archive ID
31527
Model history 21 other years
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Manufacturer catalog

Published sizes and colors

7 sizes · 2 colors

Manufacturer-published sizes and colors; availability and exact size/color pairings may vary by market or production run.

Published sizes

13"15.5"17.5"19.5"21.5"womens 13"womens 17.5"

Published colors

Black/RedBlue/Silver

Frameset

Frame ConstructionTIG-welded
Frame MaterialHi-tensile steel
ForkRST 191 CL, 63mm travel
Fork MaterialAluminum, single crown

Drivetrain

Component GroupMountain Mix
ShiftersShimano Altus EF-29
Front DerailleurShimano C051
Rear DerailleurShimano Altus
CranksetSuntour XCC-100, 28/38/48 teeth
Rear Cogs7-speed, 13 - 30 teeth
Chain1/2 x 3/32"
PedalsNylon platform

Brakes

BrakesAluminum linear-pull brakes, aluminum linear-pull levers

Cockpit & Contact Points

Headset1 1/8" threadless Aheadset
HandlebarAluminum, 1.25" rise
Handlebar ExtensionsNot included
StemAluminum threadless
SaddleBontrager Sport
SeatpostAluminum micro-adjust

Wheels & Tires

HubsAluminum, Q/R
RimsMatrix 550, 32-hole
SpokesStainless steel, 14ga. (2.0mm) straight gauge
Spoke NipplesBrass nipples
Front Tire26 x 2.00" Bontrager Connection
Wheel Size26" wheels

Historical reference geometry

Geometry

Legacy reference · 6 measurements

This historical geometry describes the model, but the original source does not identify its frame size. Use it as a period reference, not a size-specific fit comparison.

MeasurementLegacy reference
Top tube556.3 mm
Head-tube angle70.5°
Seat-tube angle73°
Chainstay / rear center435 mm
Wheelbase1039 mm
Fork offset / rake38.1 mm

The preserved source contains one model-level geometry set without an identified frame size.

Published drivetrain ratios

Gearing

Chainring ÷ rear sprocket

Lower ratios provide more mechanical advantage for climbing. Higher ratios turn the rear wheel farther with each crank revolution.

Published build48/38/28T · 13–30T · 7-speed
Lowest0.93:1 Highest3.69:1 Total range396%

The bar uses the same mechanical-ratio calculation as Compare. Wheel-dependent speed appears only when the record includes an exact ISO/ETRTO rear tire size; no tire size is assumed.

Parts & serviceability

Find replacement parts

3 top part searches
Front tireMatching fit standard
26x2.00" Bontrager Connection Named tire and published size
Brake padsMatching fit standard
Linear-pull brake pads Published brake type — verify pad mounting style
SaddleQualified part search
Bontrager Sport Named archived component — verify exact version
More qualified parts (2)
Rear derailleurMatching configuration
Shimano Altus Interpreted as Shimano Altus · 7-speed · mechanical Named component · published drivetrain speed — verify exact version
ShiftersQualified part search
Shimano Altus EF-29 Interpreted as Shimano Altus · 7-speed · mechanical Named component · published drivetrain speed — verify exact version

Searches use the archived manufacturer specification, not the components currently installed on a particular bicycle. Confirm the exact model, size and fit before ordering. As an Amazon Associate I earn from qualifying purchases. Velopedia may also earn from qualifying eBay purchases. Velopedia may also earn from qualifying retailer purchases. Commercial relationships do not influence Archive specifications or analysis.

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Bike-specific inspection checklist 20 checks based on 6 archived component groups Open checklistClose checklist
0 of 20 checked Progress stays in this browser for this bike.

This checklist uses the archived equipment for this bike. It cannot confirm the condition, service history or later component changes of the example in front of you.

Archived: 2004 Trek 820 · Mountain bike, front suspension · Published sizes: 13", 15.5", 17.5", 19.5", 21.5", womens 13", womens 17.5"

Archived: Frame: TIG-welded · Fork: RST 191 CL, 63mm travel · Aluminum, single crown

Archived: Fork: RST 191 CL, 63mm travel

Archived: Group: Mountain Mix · Shifters: Shimano Altus EF-29 · Front derailleur: Shimano C051 · Rear derailleur: Shimano Altus · Crankset: Suntour XCC-100, 28/38/48 teeth · Rear cogs: 7-speed, 13 - 30 teeth · Chain: 1/2 x 3/32"

Archived: Brakes: Aluminum linear-pull brakes, aluminum linear-pull levers

Archived: Wheel size: 26" wheels · Rims: Matrix 550, 32-hole · Hubs: Aluminum, Q/R · Front tire: 26 x 2.00" Bontrager Connection

Controls and contact points

Archived: Headset: 1 1/8" threadless Aheadset · Handlebar: Aluminum, 1.25" rise · Stem: Aluminum threadless · Seatpost: Aluminum micro-adjust · Saddle: Bontrager Sport · Pedals: Nylon platform

Before and during the test ride

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Specifications are presented as a reference. Components may vary by market, size, production run, or later manufacturer revisions.

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